The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 20, 1990
Filed:
Dec. 04, 1987
Akos Bodnar, Balatonfured, HU;
Maria Solymoss, Veszprem, HU;
Ibolya Vancson Szmercsanyi, Budapest, HU;
Istvan Szigeti, Veszprem, HU;
Laszlo Szommer, Fuzfogyartelep, HU;
Nitrokemia Ipartelepek, Fuzfogyartelep, HU;
Abstract
The invention relates to the acceleration of the synthesis of unsaturated polyesters containing maleic acid/anhydride, 1 to 30 percent, preferably 5 to 15 percent of the prescribed maleic acid/anhydride is introduced into the reaction mixture in total or in two or more increments at the stage of the reaction when the acid number or the molecular weight of the mixture has reached about 50 to 250 or about 300 to 1500, respectively. Thus, the rate of polyesterification can be increased considerably, occasionally two-folds and, in addition, polyester resins of very low acid number or high molecular weight can be prepared.